1. Field of the Invention
The present invention relates to the field of portable terminals, and more particularly, to a portable terminal having a hinge apparatus which couples a pair of housings to each other such that the pair of housings can rotate while facing each other.
2. Description of the Related Art
Generally, a “portable terminal” is an electronic apparatus that provides wireless communication between users or between users and service providers. Mobile communication services using portable terminals have been limited to voice communication and short text transmission services in the initial stage of development, but they are rapidly expanding and now include multimedia services such as online games and video-on-demand services, and data services such as transmission of moving picture files/music files.
Portable terminals may be classified as bar-type terminals, flip-type terminals, and folder-type terminals according to their appearance. In a bar-type terminal, input devices such as a keypad and a transmitting unit (or mouthpiece) and output devices such as a display device and a receiving unit (or earpiece) are mounted in a single housing. In a flip-type terminal, a flip cover is rotatably mounted to prevent malfunctioning of input devices that may occur due to mounting of input/output devices in a single housing. In a folder-type terminal, two housings sections are coupled such that they rotate toward or away from each other while facing each other. Input devices and output devices are separately disposed in the housings, thereby facilitating the use of the terminal and making it easy to carry the terminal in a folded state.
In addition, a sliding-type terminal is opened and closed by a linear movement of a pair of housings facing each other, while a swing-type terminal is opened and closed by rotation of a pair of housings facing each other. A folder-type terminal is opened and closed by a movement of a front with respect to a rear surface. A rotary-type terminal combines the opening/closing operations of a folder-type terminal with the opening/closing operations of a swing-type terminal. This type of terminal meets various user preferences.
U.S. patent application Ser. No. 10/287,148 filed on Nov. 4, 2002 (issued as U.S. Pat. No. 7,200,409) by the present applicant discloses a swing-type terminal in which two housings are coupled to rotate while facing each other, and a hinge apparatus thereof. The hinge apparatus of the swing-type terminal includes a first hinge base and a second hinge base having a hinge shaft which is rotatably coupled to the first hinge base through a hinge hole of the first hinge base. An engagement means such as an E-ring is coupled to an outer circumferential surface of the hinge shaft.
The hinge apparatus of the swing-type terminal includes a body portion from which the hinge shaft extends, the body portion being fixed to a housing, and a rotating portion fixed to the other housing and rotatably coupled to a shaft of the body portion. The body portion and the rotating portion are prevented from being separated by using engagement means such as an E-ring and a snap ring.
However, conventional portable terminals performing swing operations may produce unpleasant noise due to interference between housings during rotation of the housings with respect to each other, and may suffer from damage to the exteriors of the housings due to a scratch or the like. Moreover, if a foreign substance is introduced between the housings, the exterior damage due to a scratch or the like worsens.